Dear Prashant and Rashida
There appear to be some variations in different floras.
I think we have discussed this earlier when I had posted images from Pune.(Last flowers at present of this season)According to BSI Flora Maharashtra. S.colais is synonymous with S.personatum.
So I think you are right. The genus Stereospermum has been divided as per following key.
1. Panicle branches viscid hairy ... ... S.chelenoides
2. Panicle branches glabrous : 2. Leaflets caudate at apex; corolla wooly at base ... ... S.colais
var. colais 2. Leaflets acuminate at apex; corolla not wooly at base ... S. colais
On studying various pictures I think Prashant's plant has acuminate leaflets and corolla not wooly..
...so it is likely to be S.colais var angustifolium.
Regarding Rashida ji's plants. I think the leaflets of the plant from Mumbai are clearlly caudate and those from Anshi have different apex of the leaflet(Not classic caudate)
Again I suppose main importance is given to the wooliness at the base of corolla which is difficult to percieve. Will get help from Rahida ji about key from Almeida's flora.